Hormone leptin could aid in body weight loss

A new study offers insight into why it's easier to lose weight than to keep it off for good.

&to=http://english.pravda.ru/main/18/90/360/10635_medicine.html' target=_blank>Body weight is regulated by metabolic, neuroendocrine, and autonomic systems, which work together to restore fat mass in people who've lost weight, the study authors concluded. That's because the body interprets reductions in weight as a deficiency in the hormone leptin.

These mechanisms explain why more than 85 percent of obese people who've lost weight eventually regain those pounds, the Columbia University researchers said.

They tested this theory by giving "replacement" doses of leptin to obese people and to lean people who'd just lost weight. The leptin doses reversed most of the metabolic, neuroendocrine and autonomic changes that occur in an effort to counter reduced body weight, reports Forbes.

Dr Rosenbaum's team looked at the effects of leptin on ten healthy volunteers. As the men and women lost weight, their &to=http://english.pravda.ru/science/19/94/377/15971_diabetes.html' target=_blank>leptin levels fell. But giving them leptin allowed them to stick to their new weight, the study, published in the Journal of Clinical Investigation, found.

Previous studies have shown that leptin acts as an appetite suppressant. Research last year showed that when we don't get enough sleep, our levels of leptin fall and we feel the urge to eat more.

Leptin is one of many chemicals released during sleep and it is thought that losing just an hour or two of sleep a night is enough to cause a significant dip in levels of the hormone.